Head and neck cancer patients are increasingly being diagnosed at earlier ages and surviving their cancers at elevated rates compared to historic cohorts. This is leading to an expanding population of head and neck cancer survivors, many of whom will suffer from the significant long-term effects of treatment. Of these late health effects, oral health problems consistently rate among the most detrimental to patient quality of life. However, limited data regarding the true prevalence of these effects is missing, particularly for long-term cancer survivors. While prior research has evaluated the prevalence in small, institutional series, population- level studies that are able to provide a better estimate of the true burden of these problems are limited and consist only of SEER-Medicare studies that exclude patients under the age of 65. Given the increasingly earlier age of diagnosis of head and neck cancer patients, it remains unknown how pervasive these late effects are in this population, what patients are most at risk, how that risk evolves over time, and what the impact of these late effects are to patient quality of life. The State of Utah has a unique epidemiologic resource, the Utah Population Database, that provides access to the medical records capturing ~90% of the state's population. This database is linked with the State's cancer registry, All Payers Claims Database, genealogy records, and Utah's Department of Health Records. From this database we have assembled a comprehensive and well-characterized population-based cohort of over 1,900 head and neck cancer patients with long-term follow-up. We propose an evaluation of oral health late effects in our population-based cohort of head and neck cancer survivors. To our knowledge, this cohort is the first of its kind in the United States. We will assess the prevalence and risk of developing oral health diagnoses over clinically relevant post-diagnosis time points through a combination of data from the linked databases, medical records abstraction, and patient provided information. The impact of oral health problems on quality of life will be assessed with validated general, disease-specific, and oral health specific quality of life instruments. Finally, these data will be used to develop risk prediction models for late health problems of particular clinical relevance, thereby translating the study findings into clinically useful tools. This study will provide information that will be of great benefit to the expanding population of head and neck cancer survivors by directly informing patient counseling, impacting treatment decisions, and identifying at-risk survivor subgroups that will benefit from personalized health interventions.